AMI_Event::addHandler('on_before_form_field_{status}', 'handleOrderFormStatusField', 'eshop_order');

function handleOrderFormStatusField($name, array $aEvent, $handlerModId, $srcModId) {
    $aDisabled = array('pending', 'accepted', 'draft', 'cancelled');
    $aData = array();
    for($i = 0; $i < count($aEvent['aField']['data']); $i++) {
        if(!in_array($aEvent['aField']['data'][$i]['value'], $aDisabled)) {
            $aData[] = $aEvent['aField']['data'][$i];
        }
    }
    $aEvent['aField']['data'] = $aData;
    return $aEvent;
}